commitmonitor Code

Make using TortoiseSVN for showing the diffs optional.

Add a ".diff" extension to the unified diff files.
This implements issue #40.

* Refactor the child window positioning code out from OnLButtonUp() into PositionChildWindows()
* Store/Restore the slider positions on dialog show/hide.

This implements issue #32.

Before using the project name in a path, convert all special chars.
This fixes issue #35.

If no author or date is available, show "(no author)" or "(no date)" instead of an empty string or a bogus date.

Speed up the loop by moving ListView_GetItemCount() outside the loop.

When selecting a project in the tree control and filling the revision list control, ensure that the first unread item is visible.
This implements issue #31.

Improve the diff function if TortoiseSVN is installed:
* if TSVN is installed, add a second entry to the log list control context menu for diffing with TSVN.
* if TSVN is installed, the default diff uses TSVN.
* to get the unified diff again (if TSVN is installed), the log list control context menu entry "show unified diff" has to be used.

This implements issue #13 (kind of).

If no unified diff viewer is specified and TortoiseSVN is installed, use TortoiseSVN to do and show the diff.

When selecting a tree item which has no error, remove the list control info text.